Smitha Gopinath^1,2, A. Ramachandra Murthy¹, Bhaskar Srivastava¹, V. Ramesh kumar¹, Nagesh R. Iyer¹

CMC-Computers, Materials & Continua, Vol.27, No.1, pp. 73-100, 2012, DOI:10.3970/cmc.2012.027.073

Abstract The present study investigates the behavior of concrete specimens confined with woven roving glass fabrics under uniaxial compression. The fabric made up of 360G.S.M. woven roved E-glass is embedded in a polyester resin before application. Experimental investigations have been carried out on confined and unconfined concrete specimens of size 150 mm (diameter) X 300 mm (height) under a displacement controlled loading. The effect of number of layers on confinement has also been investigated. Load versus deflection plots have been obtained for all the specimens. Numerical studies have been performed on the confinement effect of the… More >

Bhashya V.¹, Ramesh G.¹, Sundar Kumar S.¹, Bharatkumar B. H.¹, Krishnamoorthy T.S.¹, Nagesh R Iyer.¹

CMC-Computers, Materials & Continua, Vol.25, No.1, pp. 47-74, 2011, DOI:10.3970/cmc.2011.025.047

Abstract Fibre-reinforced polymers (FRPs) are being introduced into a wide variety of civil engineering applications. These materials have been found to be particularly attractive for applications involving the strengthening and rehabilitation of existing reinforced concrete structures. In this paper, experimental investigations and analytical studies on four series of the concrete cylinders wrapped with FRP are presented. First series consist of concrete cylinders wrapped with one layer carbon fiber reinforced polymer (CFRP), second series concrete cylinders wrapped with two layers CFRP, in third series, concrete cylinders were wrapped with one layer glass fiber reinforced polymer (GFRP) and… More >

Yana Wang^1,2,3,4, Ruodi Jia^1,5, Fengrui Liu^1,5,6,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 215-234, 2019, DOI:10.32604/cmes.2019.06542

Abstract Delamination and matrix cracking are two common failure mechanisms in composite structures, and are usually coupled with each other, leading to multiple failures pattern. This paper proposed a fast damage prediction methodology for composite laminated structures based on the ply-by-ply 2D (two dimensional) FE model of composite laminates in the transverse plane. The layer-wise 2D FE model was firstly used in conjunction with the integrated XFEM/CE strategy, which simulated the interface delamination with cohesive elements and the intra-ply matrix crack with XFEM (extended finite element method). To realize ply-by-ply 2D FE (finite element) modeling of More >

W.H. Chen¹, H.C. Cheng^2,3, C.F. Yu^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.109-110, No.1, pp. 1-13, 2015, DOI:10.3970/cmes.2015.109.001

Abstract This study aims at exploring the interfacial adhesion strength between solder bump and four typical under bump metallurgies (UBMs), i.e., Cu/Ni, Cu/TiW, Cu/Ni/Cr and /Cu/V/Cr, at atomistic scale. The average bond length and interfacial adhesion stress of the Sn-3.5Ag/Cu/Ni, Sn-3.5Ag/Cu/TiW, Sn-3.5Ag/Cu/Ni/Cr and Sn-3.5Ag/Cu/V/Cr micro-bump interconnects are calculated through the firstprinciples density functional theory (DFT) calculation to estimate the interfacial adhesion strength between the solder bump and UBMs. In addition, by investigating the electric field effect on the average bond length and adhesive stress, the combination of solder bump and UBM with better interfacial adhesion strength… More >

Xuwen An^1,2, Jianguo Hou³, P.D. Gosling⁴, Dong Dai⁵, Long Xiao⁶, Xiaoyi Zhou⁷

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.1, pp. 1-25, 2015, DOI:10.3970/cmes.2015.107.001

Abstract Studies on the theory of structural system reliability includes identification of main the failure modes and calculation of inclusive failure probabilities for the structural system. The efficient and accurate identification of failure modes in structural systems is difficult and represents a key focus for research in system reliability. The fundamental theory of the branch and bound algorithm for stage critical strength is reviewed in this paper. Some deficiencies in this method are highlighted. Corresponding approaches to overcome these deficiencies are proposed. Calculated system reliability solutions to the classical model, a truss with 10 elements, indicate More >

Joo Shin Park¹, Jung Kwan Seo^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.4, pp. 291-308, 2015, DOI:10.3970/cmes.2015.106.291

Abstract Ships, ship-shaped offshore structures, land-based structures and aerospace structures typically consist of various curved plate components. It is difficult to simulate the buckling and post-buckling of curved thin and/or thick plates that have characteristics of nonlinear structural mechanics, such as nonlinear behaviour when loading is applied. The elastic post-buckling behaviour of a curved plate is very complex, and accompanied by mode changes due to the occurrence of secondary buckling behaviour. Therefore, it is very important to clarify the elastic post-buckling behaviour when subjected to axial loading. The aim of this study was to derive an More >

Shantaram Parab¹, Shreya Srivastava², Pijush Samui³, A. Ramachandra Murthy⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.2, pp. 139-158, 2014, DOI:10.3970/cmes.2014.101.139

Abstract This paper studies the applicability of Gaussian Process Regression (GPR) and Least Squares Support Vector Machines (LSSVM) to predict fracture parameters and failure load (P_max) of high strength and ultra-high strength concrete beams. Fracture characteristics include fracture energy (G_F), critical stress intensity factor (K_IC) and critical crack tip opening displacement (CTOD_C) Mathematical models have been developed in the form of relation between several input variables such as beam dimensions, water cement ratio, compressive strength, split tensile strength, notch depth, modulus of elasticity and output fracture parameters. Four GPR and four LSSVM models have been developed using MATLAB… More >

K.Y. Volokh^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.1, pp. 87-101, 2013, DOI:10.3970/cmes.2013.092.087

Abstract In the laminar mode interactions among molecules generate friction between layers of water that slide with respect to each other. This friction triggers the shear stress, which is traditionally presumed to be linearly proportional to the velocity gradient. The proportionality coefficient characterizes the viscosity of water. Remarkably, the standard Navier-Stokes model surmises that materials never fail – the transition to turbulence can only be triggered by some kinematic instability of the flow. This premise is probably the reason why the Navier-Stokes theory fails to explain the so-called subcritical transition to turbulence with the help of… More >

A. Ramachandra Murthy¹, Nagesh R. Iyer¹, B.K. Raghu Prasad²

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.6, pp. 459-480, 2012, DOI:10.3970/cmes.2012.089.459

Abstract This paper presents the details of crack growth study and remaining life assessment of concrete specimens made up of high strength concrete (HSC, HSC1) and ultra high strength concrete (UHSC). Flexural fatigue tests have been conducted on HSC, HSC1 and UHSC beams under constant amplitude loading with a stress ratio of 0.2. It is observed from the studies that (i) the failure patterns of HSC1 and UHSC beams indicate their ductility as the member was intact till the crack propagated up to 90% of the beam depth and (ii) the remaining life decreases with increase… More >

Mark Andrew Bradford¹, Yong-Lin Pi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.5, pp. 389-416, 2012, DOI:10.3970/cmes.2012.089.389

Abstract This paper is devoted to the development of a finite composite beam element for the nonlinear elastic-plastic analysis of composite high strength steel and geopolymer concrete members. For this, geometric nonlinearity is derived using a special orthogonal rotation matrix, so that scalar product of vectors is preserved during rotation from the initial configuration to a deformed configuration and rigid body movements are excluded from the finite strains. The material nonlinearities of the geopolymer concrete are based on constitutive models in association with its axial stress-strain relationship that is consistent with the experimental results. To consider… More >